#!/bin/sh

set -eu

: "${DISK:=/dev/sdc}"

readonly SCRIPT="${0##*/}"
readonly TMPDIR="$(mktemp -dt "${SCRIPT%.*}".XXXXXX)"
readonly BOOTDEV="$DISK"1
readonly ROOTDEV="$DISK"2
readonly APK_KEY="alpine-devel@lists.alpinelinux.org-60ac2099.rsa.pub"
readonly MIRROR="http://dl-cdn.alpinelinux.org/alpine"

cleanup() {
	set +e
	mountpoint -q "$TMPDIR"/boot && umount "$TMPDIR"/boot
	mountpoint -q "$TMPDIR" && umount "$TMPDIR"
	rm -rf "$TMPDIR"
}

trap cleanup EXIT INT
model='j293'
kernver='5.16.0-rc5-a5'
kernel="linux-$kernver.tar.gz"

if [ ! -f m1n1.macho ]; then
	wget https://dev.alpinelinux.org/~mps/m1/m1n1.macho
fi

if [ ! -f $kernel ]; then
	wget https://dev.alpinelinux.org/~mps/m1/"$kernel"
fi

echo "Paritioning disk"
parted -s "$DISK" mktable gpt > /dev/null
parted -s "$DISK" unit s -- mkpart primary ext4 2048 1050623 > /dev/null
parted -s "$DISK" unit s -- mkpart primary f2fs 1050624 7888862 > /dev/null

echo "Creating dirs and mounting"
mkfs.ext4 -qL boot "$BOOTDEV"
mkfs.f2fs -fl root "$ROOTDEV"
mount -t f2fs "$ROOTDEV" "$TMPDIR"
mkdir -p "$TMPDIR"/boot
mount -t ext4 "$BOOTDEV" "$TMPDIR"/boot
mkdir -p "$TMPDIR"/boot/extlinux "$TMPDIR"/etc/apk/keys

echo "Setup apk keys and repositories"
#wget -qP "$TMPDIR"/etc/apk/keys https://alpinelinux.org/keys/"$APK_KEY"
printf "$MIRROR/edge/%s\n" main community > "$TMPDIR"/etc/apk/repositories

echo "installing base packages"
apk --allow-untrusted --root "$TMPDIR" --arch aarch64 --initdb add \
	alpine-base alpine-baselayout alpine-conf kmod openrc \
  linux-firmware-none util-linux blkid \
	sysfsutils ssl_client ca-certificates-bundle alpine-keys \
	openssh-server f2fs-tools ethtool e2fsprogs libudev-zero libudev-zero-helper \
	wpa_supplicant iwd

partuuid=`blkid -o value -s PARTUUID $ROOTDEV`
echo $partuuid
bootargs="boot-args=root=PARTUUID=\"$partuuid\" rootwait"
echo $bootargs
tar xf $kernel -C $TMPDIR
gzip $TMPDIR/boot/vmlinux-$kernver
#cat m1n1.macho <(echo 'boot-args=root=PARTUUID=3d20affd-c082-421b-a111-f5d6b1587fe4 rootwait') ak4.gz ak4.dtb > m1n1-payload.macho
cat m1n1.macho <(echo $bootargs) $TMPDIR/boot/vmlinux-$kernver.gz $TMPDIR/boot/dtbs-$kernver/apple/t8103-$model.dtb > m1n1-payload.macho
console='console=${console}'
echo "Creating extlinux.conf"
cat > "$TMPDIR"/boot/extlinux/extlinux.conf<<EOF
TIMEOUT 50
PROMPT 1
DEFAULT sunxi

MENU TITLE Alpine on M1

LABEL asahi
MENU LABEL sunxi
KERNEL /vmlinux-$kernver
FDTDIR /dtbs-apple
APPEND modules=sd-mod,usb-storage,ext4,f2fs,sunxi-mmc root=PARTUUID=\"$partuuid\" rw rootwait $console
EOF
#INITRD /initramfs-edge-virt
#echo "PARTUUID=$BOOTPART	/boot    ext4	auto" >> "$TMPDIR"/etc/fstab

echo "Setting up services and inittab"
for rc in boot/bootmisc boot/hostname boot/modules boot/sysctl boot/urandom boot/networking \
	sysinit/devfs sysinit/hwdrivers sysinit/mdev sysinit/modules \
	shutdown/mount-ro shutdown/killprocs; do
	ln -s /etc/init.d/"${rc##*/}" "$TMPDIR"/etc/runlevels/"$rc"
done

sed -i 's/^#ttyS0/ttyS0/' "$TMPDIR"/etc/inittab

echo "Finished, cleaning up"